What's the difference between Plantar Fasciitis and Plantar Fasciotis?

One is an inflammed plantar fascia, the other is a degenerated plantar fascia.

Plantar fasciitis is one of the most common causes of heel pain. It involves pain and inflammation of a thick band of tissue, called the plantar fascia, that runs across the bottom of your foot and connects your heel bone to your toes.  It is characterised by stabbing pain that usually occurs with your very first steps in the morning.  The pain normally decreases with movement, but it may return after long periods of standing or after getting up from a seated position.  Plantar fasciitis is particularly common in runners. In addition, people who are overweight and those who wear shoes with inadequate support are at risk of plantar fasciitis.

Plantar fasciosis is the term used to describe the degenerated and non-inflamed phase of plantar fasciopathy (heel pain) caused by the degeneration (deterioration) of the plantar fascia which often occurs as a result of repetitive stress.